Power steering systems are commonly employed in vehicles to assist drivers. Indeed, power steering systems are now the norm with customers expecting trouble free operation.
During vehicle manufacturing and assembly, and particularly during initial engine run-in, there exists a high likelihood that impurities may be introduced into the system. These impurities can range from small metallic pieces to large dust and dirt particles. That fact is especially true in cases of hydraulic fluid lines, implemented throughout the vehicle for a varied set of application, such as the steering system.
Debris in the hydraulic steering system may circulate through the fluid lines during the initial stages of the vehicle's operation. Any condition where an impurity lodges in the system, whether in the hydraulic steering pump or any other component, the resulting obstruction may choke the fluid flow, leading to major failures. Damages involved in such cases may be irreversible and may lead to a complete component replacement. Even if the blockage does not affect components directly, it may choke the fluid flow, affecting the resultant work output of the components, leading to inefficiencies in the system.
Conventional methods for removing contaminants generated during engine run-in, attempted at a later time such as during vehicle repairs or service, are ineffective and time consuming. Some equipment manufacturers address this problem by employing a temporary filter when first operating the hydraulic steering. That approach can be problematic, because temporary filters rapidly become redundant. Further, where permanent filters remain in the system, they produce ongoing pressure losses. That state becomes worse during low temperature conditions, where increased fluid viscosity requires higher energy from the engine for effective circulation. Also, the cost of a permanent filter arrangement makes that solution unattractive for mass manufacturing. Similarly, solutions employing a pressure activated filter bypass mechanism cause overall pressure losses, resulting in higher energy consumption.
Thus, the need remains for an improved, energy efficient, inexpensive system that effectively removes contaminants from a vehicle's hydraulic steering system during engine run-in all without affecting long-term efficiency